Abstract
Abnormalities in the adhesion of platelets to connective tissue have received little recognition. A striking abnormality in platelet adhesion to collagen was demonstrated in a patient with a bruising tendency.
A 26-year-old woman visited our hospital complaining of easy bruising on the limbs and trunk from early childhood. Physical examination revealed a healthy and well-developed woman except for some purpurous lesions on the limbs. Coagulation analysis revealed slightly prolonged bleeding time, mildly increased capillary fragility, and markedly defective platelet adhesion to collagen with poor collagen-induced aggregability. On the other hand, platelet-counts, platelet aggregabilities with adenosine diphosphate (ADP), adrenaline, arachidonic acid, ristocetin and bovine fibrinogen, release of platelet ADP, analysis of platelet membrane glycoproteins, and tests of coagulation/fibrinolysis were all normal.
It is suggested that a striking defect of the platelet-collagen interaction, diagnosed as collagen adhesion abnormality or collagen ineffectiveness, might be responsible for the bleeding tendency in this patient.
